See also
https://www.healthline.com/health/happy-hormone
https://www.amazon.com/-/zh_TW/Loretta-Graziano-Breuning/dp/1463790929/ref=mp_s_a_1_1?dchild=1&keywords=Meet+Your+Happy+Chemicals%3A+Dopamine%2C+Endorphin%2C+Oxytocin%2C+Serotonin&qid=1626751647&sr=8-1 (accessible via scribd)
